Seven fighters from the Hashed al-Shaabi, also known as the Popular Mobilisation Forces (PMF) and now part of the regular armed forces, were "killed and 13 wounded in a US strike" targeting their base in western Anbar province, a PMF source said.

They added that the bombing occurred during a commanders' meeting, with some people "still trapped under rubble".

A security official told AFP that the wounded were being treated at a hospital.

A PMF statement condemned the strike, saying it had killed a commander and a number of fighters, but did not give further details.

Iraq has been unwillingly pulled into the war triggered by Israel and the United States striking Iran on February 28.

Since the start of the conflict, Baghdad has repeatedly denounced attacks on the Hashed al-Shaabi, which also includes brigades belonging to Iran-backed groups.

Pro-Iran armed groups have claimed responsibility for attacks on US interests in Iraq and across the region, while strikes have also targeted these groups.

Last week, the Pentagon acknowledged for the first time that combat helicopters had carried out strikes against pro-Iran armed groups in the country during the latest conflict.